render mesh

Apologies in advance for the dumb question. I'm getting a wall rendered over existing and one of the people quoting suggested pinning render mesh to the existing render. Stupidly, I forgot to ask him what this meant so now I'm curious. What pins are used and how are they applied?

Hi all, hoping some could give me some advice please on best solutions to repair my external cracks and re-render the elevation. I’m getting slightly mixed advice from builders on the best approach and am a bit uncertain of which way to go. Some saying to go with a stainless steel mesh which is...